textproduct: Quad Cities

KEY MESSAGES

- Widespread rainfall will continue this afternoon into the evening hours before waning later this evening. Rainfall amounts so far have been lower than expected, which should help limit the flash flooding threat, and we have dropped the Flood Watch for areas along and south of Highway 34.

- Weak disturbances and northwesterly flow aloft to keep temperatures comfortable and slightly below average through the end of the week.

SHORT TERM /THROUGH MONDAY/

Issued at 238 PM CDT Sun Jun 21 2026

Early this afternoon, we continue to see widespread showers over the area as a low pressure system translates over northeastern Missouri, with an attendant mid-level shortwave impulse aloft. Soaking rainfall over much of the area associated with an MCV this morning brought rainfall amounts reported of 1 to 1.5+ inches along and south of Highway 34, which is below the local flash flood guidance values in those area. With little in the way of additional rainfall across our south per the latest upstream radar imagery, we have decided to drop the Flood Watch early. There could still be some flooding impacts due to rises on local creeks and rivers. Additionally, with the fact that the surface low will remain south of our area, the bulk of the instability should stay to our south, so there isn't expected to be much recovery in the wake of the MCV for robust convection to develop along the surface low, so SPC has pulled the Marginal Risk (level 1 of 5) of strong/severe storms completely out of our southern forecast area.

As we go into the evening hours, even though the surface low is expected to depart the region to the east, some lingering light rain showers should remain as the mid-level shortwave and 850-700 mb layer FGEN forcing persists for a little while longer. However, these lingering showers should taper off as the large-scale forcing moves out and drier air slowly filters in as an area of high pressure builds. This will support a period of drier conditions for Monday, with continued northerly flow. Daytime highs Monday are expected to warm to the middle to upper 70s, under partly to mostly sunny skies.

LONG TERM /MONDAY NIGHT THROUGH SATURDAY/

Issued at 238 PM CDT Sun Jun 21 2026

The long term forecast period remains active through the end of the week, with a few additional shortwaves expected to sweep through the area. Monday night and Tuesday appear to remain dry over the area, with seasonably cool conditions with highs warming up to the upper 70s for most Tuesday. The first shortwave will then eject towards the Corn Belt region Tuesday night on the northern side of upper- level anticyclonic flow anchored over northern Mexico. While southerly return flow around the surface high pressure system over the western Great Lakes will help dew points increase to the middle 60s by Wednesday, precipitation amounts remain more limited with the Tuesday night shortwave given a lack of robust moisture. There appears to be a signal for at least better moisture on Wednesday concurrent with a surface cold front progged to sweep through the area, with the LREF ensemble showing exceedance probabilities of a tenth of an inch around 50 to 70% along and north of Interstate 80 and the RRFS Pwat values around 1.2 to 1.6".

High pressure looks to build back in for Wednesday night through Thursday, which should support another dry day, with continued seasonably cool conditions. There are some signals for increasing chances (20-40%) of showers and storms for late this week, but there is some uncertainty on the timing and coverage of this activity, given differences among the model guidance.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1243 PM CDT Sun Jun 21 2026

Messy flight conditions will continue this afternoon, with a mix of MVFR/IFR ceilings and visibilities under an area of moderate to heavy rain. Confidence is quite low on how these conditions will evolve as conditions appear to be waffling between MVFR/IFR, so we have introduced TEMPO groups to at least help pin down timing of when these conditions could be changing. Forecast confidence begins to increase this evening as the rain starts to taper off, leading to a period of MVFR conditions before transitioning to VFR overnight into Monday morning. Easterly winds as of TAF issuance should gradually turn more northeasterly this afternoon as an area of low pressure moves through northern Missouri/west-central Illinois. As winds weaken overnight, they will continue to turn more northerly through the end of the TAF period.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.